Piano.



W. L. BJUR.

PIANO. 'APPLIoATIoN FILED un. a, 1910.

Patented Aug. 9, 1910.

.n hm

ma ron-Ris PETERS ca., wAsmNcrcN. n4 c UNITED STATES PATENT OFFICE.

WILLIAM L. BJUR, OF NEW YORK, N. Y.

PIANO.

To all whom fit may concern:

Be it known that I, VILLIAM L. BJUR, of the borough of Manhattan, city,county, and State of New York, have invented certain new and usefulImprovements in Pianos, of which the following is a full, clear, andexact specification, such as will enable others skilled in the art towhich it appertains to make and use the same.

My invention relates to an improvement in the construction of the framework of pianos, particularly upright or vertical pianos. Usually suchpianos have a heavy wooden back in the upper part of which is arranged alaminated pm block carrying the pins by which the strings are fastenedand the whole being fastened to the back by heavy lag screws. The top isfinished off to expose the laminations of the pin block to view and theback is braced by vertical beams or scantlings. This method ofconstruction is expensive in the finishing of the top of the pin block;the lag screws for fastening the pin block do not always properly servetheir purpose and the scantling or beams at the back are unsightly.

The object of my invention is to overcome these disadvantages and to soorganize the frame of the piano at the points referred to that thelaminations of the pin block may be made to appear without the expenseof finishing the rough wood-ends, the pin block fastened through thewhole thickness of the back by a special nut and bolt and the backinclosed in a neat and artistic manner without, however, impairing theacoustical properties of the instrument. I attain these ends by certainindividual features of construction and combination of parts which willbe fully set forth hereinafter and particularly pointed out in theclaims.

For this purpose reference is had to the accompanying drawing, whichrepresents, as an example, the preferred embodiment of my, invention andin whichw Figure 1 is a rear view of the piano embodying my invention;and Fig. 2 is a vertical section of the upper part of the frame of thepiano, excepting that the top cover or lid is removed.

In these drawings-10 indicates the back of the piano which is of massivewood and 11 indicates the string plate which is of iron. The pin blockis composed of a main lamination 12 and a number of minor laminations122L which together constitute the Speeication of Letters Patent.

Application filed March 8, 1910.

Patented Aug. 9, 1910.

sei-iai No. 548,010.

built-up pin block. The laminations 121 are placed with their graincrossing so that they constitute an extremely tough body of wood intowhich the string pins 14 are driven and by which such pins are firmlyheld, notwithstanding the extremely heavy strain imposed upon them bythe tension of the piano strings.

F or fastening the pin block in place and for holding the string plateproperly in position I employ peculiar back bolts which are representedat 15 in the drawing. These bolts have heads 15a integral therewith andbearing against the face of the string plate. Said bolts extend throughthe string plate, pin block and back and are engaged at the very back ofthe piano with special nuts 16. These nuts are counter-sunk into theback 10 and are furnished with ribs 16L driven into the back to preventthem from turning and a fiange 1Gb engaging the face of the back 10.Each nut 16 has two bearings facing in the same direction, one bearingbeing at the inner end of the nut to draw against the bottom of thecounterbore and another bearing at the inner face of the flange 16barranged to draw against the rear surface of the back 10. This allowsthe back bolt to be tightened to the necessary degree of tension andenables all the parts held by such bolt to be drawn most firmlytogether.

It is customary in the construction of upright pianos to finish off t-hewood-ends at the upper edge of the frame showing` a back and pin blockin a highly polished state exposing the laminations of the latter. This,however, is expensive and difficult and I have effected the same resultby the provision of a heavy veneer 17. This veneer is of the same woodas the back and pin block and it is formed in strips correspondingprecisely to the laminations of the pin block. The veneer 17 is glued orotherwise suitably fastened to the back and pin block and correspondsprecisely thereto, not only with respect to the laminations but to thedirection of the graining of the wood. Its surface may be readilypolished and varnished and in this way I illustrate the laminatedstructure without involving the expense of actually finishing the roughand massive woodends.

Such pianos as those to which my invention relates are usually providedwith vertical beams or scantlings at the back constituting part of theframe and between two of these beams at each side of the piano handles(shown at 18 in Fig. 1) are provided by which the piano may be moved. Inorder to render the rear of the piano symmetrical and neat in appearanceand to hide the ribbed construction I provide a thin wooden sheathing 19which covers the entire back of the piano and which is suitably fastened'thereto by glue or otherwise. It may be polished and finished and inthis way increases greatly the neatness of the piano construction. Inorder, however7 not to interfere with the acoustical properties of theinstrument large openings 20 are formed in said sheathing 19 whichopenings are preferably, though not necessarily, of oval form. Theseopenings are closed and the back of the piano practically obscured bymeans of sections of screening 21 which cover the openings and arefastened in back of the sheathing. In order to enable the handles 18 tobe reached the sheathing is also formed with openings 22 which eX- posethe handles and allow them to be easily grasped.

From the aforegoing description of my invention it will therefore appearthat by means of my improvement I have cheapened the construction of thepiano, increased its mechanical efliciency and increased its artistic orornamental effect. This is true since by applying the veneer to thewood-ends a diflicult and laborious operation has been dispensed with;by the back bolt passing clear through the back and furnished with aspecial nut I provide a much stronger construction7 and by thesheathing'19 at the back I have changed the rough and irregularconstruction heretofore employed into a neat and symmetrical surface.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent of the United States, is:

1. A piano having a back, a laminated pin block set against the frontthereof, a string plate set against the pin .block and back, a back boltextending through the string plate, the pin block and back from front torear thereof, having two bearings facing in the same direction, said nutbeing counter-sunk in the back at the rear and engaged by said back boltto hold it in place, a finished veneer applied to the top of the backand pin block and constructed of strips corresponding to the laminationsof the pin and block, a finished sheathing covering the rear surface ofthe back and formed with openings and metallic screening secured betweenthe back and said sheathing and covering said openings in the latter.

2. A piano having a back, a pin block fastened thereto and composed oflaminations of wood, the grain of the wood crossing in said laminations,and a veneer secured to the top of the back and pin block, said veneercomposed of strips of wood representing the grain and character of thewood of the back and pin block, for the purpose specified.

3. A piano having a back, a pin block and string plate, a back boltextending completely through said parts from the front to the rearthereof and a nut counter-sunk in the back and having two bearingsfacing in the same direction and both drawing against said back, saidbolt engaged with the nut to fasten it.

4. In a piano, a back, a pin block and string plate, a back boltextending through said parts from the front to the rear and a nutcountersunl in the back, said nut having two bearings spaced apart butfacing in the same direction and both drawing against said back andmeans to prevent said nut from turning in said back when in place, saidbolt engaging said nut.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

lVILLIAM L. BJUR.

IVitnesses GEORGE DERBY, GEORGE F. USBELT.

